gearboxs'!?!?

[Jony]

i need to change the gearbox in the 6, now currently it has a dolly 1850/gt6 box with i believe a Jtype overdrive, now i just want to get a gt6 box from fitchets and swap it all over, am i likely to have any issues or have to swap anything else? been looking and all the GT6 boxes seem to come with Dtype overdrives, so would it be best to get a 1850 rebuild kit? basicly its grinding and popping out of reverse, is noisy in most gears and leaks oil like a bitch, the noise (not the oil leak) has been like it since iv had it and has never really gotten any worse but needs to be sorted on my week off next week.

cheers guys

[gt5r]

Jony

 

The difference between the GT6 and the pre 1974 1850 three rail box is the mainshaft, overdrive adaptor plate and the overdrive unit. Obviously the bell housing is different but everything else is the same, gear cluster, ratio, input shaft splines all the same so it?s a straight bolt in. All GT6 have d types and 1850' had j types

 

If you have a j type in your GT then you are better off purchasing an off the shelf short (i.e. less O/D) o/d gearbox for a pre 1974 three rail 1850 dolly.

[Jony]

yes its deffinately a Jtype overdrive so just need to grab a 1850 box from fitchetts then and swap over the overdrive and bellhousing?

[Nick Jones]

Maybe..... if your existing gearbox has a fine spline (23?) input shaft that you have the internals from a later single rail Dolly box built into 3 rail casing.  This may (probably) mean that you also have the longer mainshaft and OD adaptor plate from the 1850 single rail.

 

If gearbox has the usual GT6 coarse spline then just buying a box for the early 1850 dolly should do the the business.  

 

They all piss oil out.....

 

Nick

[gt5r]

Maybe..... if your existing gearbox has a fine spline (23?) input shaft that you have the internals from a later single rail Dolly box built into 3 rail casing.  This may (probably) mean that you also have the longer mainshaft and OD adaptor plate from the 1850 single rail.

 

If gearbox has the usual GT6 coarse spline then just buying a box for the early 1850 dolly should do the the business.  

 

They all piss oil out.....

 

Nick

 

Jony - Nicks correct - as above if your box has a 10 spline 1' inputshaft and fits a standard length GT6 o/d propshaft then its 1850 pre 1974 dolly - the later shaft can be used as the tip bearing is much bigger but means you have to go to a 23 spilne friction plate and chop the prop down - although the later shaft can be used in mp opion its the least desirable way of doing it -  funny I built a box years back using a 1300 Marina gearbox longshaft and rear extention and GT6 internals - worked fine.

 

Nick - they all piss out oil - well I suppose so - thats until all the oil pisses out - then they don't leak any more   :P

[Jony]

righto i think id better get it all apart and find out exactly what it is then have a drive over to fitchetts, and theres leaking oil and pissin oil, ask smithy if he still has a rather large stain on his garage floor lol ;D

[GT6 Mike]

5 speed

[Jony]

i would if i was keeping it unless you got a gearbox + adaptor plate handy and KD is free next week

[Nick Jones]

5 speed

 

Amen to that - we only disagree on the flavour......

 

Nick

[Royboy66]

When u coming over ?

I'll get the kettle on! ;-)

[sorbs]

BW35?  It'd cut down on all that stampy pedal nonsense.

[Jango]

w58

[elsieolly]

I know Gt is bringing  some moded  boxes with close ratio 4 syncro etc to Stoneleigh but he is in the uk now at MAYNARDS Stroud. Might be worth a call

[Jony]

righto guys, got the box out, and its the 23spline one, so whats the best way to go about things? cant i just take off the bellhousing/overdrive/selector and swap it for another 23spline dolly box from fitchetts?

 

also im having a right pain getting the OD off, undone all the little nuts and got probably a 2mm gap between the OD and the adapter plate but it just wont come the rest, iv even had it hangin off the engine crane! any ideas?

 

 

cheers guys!

[Nick Jones]

23 spline means that it's single rail dolly guts built into a 3 rail case.  Unless it has a special mainshaft (which do exist but are fairly rare) it will also have the longer OD adaptor plate making it 1" longer than the usual GT6/Dtype or early Dolly/Jtype.  It's sort of good news in a way but means you won't get a bolt in replacement off the shelf.  Why don't you take your box to someone like Mick Papworth and get it sorted?

 

Don't recall problems get the OD off before - have had problems getting them to go back on though!

 

Nick

[Jony]

ye ill give him a ring tomo now! i was only going fitchetts as i was going over that way anyway and it was just a simple swap, but maybe not lol

 

thanks guys! hopefully i can get it back in by the end of the week and work starts again!

[flatter4]

 

I had a problem with spearating the two - OD clutches stuck.

If you release the adaptor to OD bolts too, the clutch should come away from the tapered mounting, and the two will separate in the normal way.

 

Let us know....

 

[Jony]

well not tried the gearbox again as i will be seeing mike tomorow anyway, but it also just so happened that in a big job lot of bits i bought ages ago was an 1850 fine spline LUK 3 peice clutch, so got that fitted today even though the old one still had plenty of life in so thats another job ticked!